Method of treating manganese steel



exposure to the air.

- with suitable reducing agents.

Patented May 29, 1928.

UNITED STATES.

VAN CORTRIGET HEKEEL,

POBATION OF NEW JERSEY.

PATENT OFFICE.

OF HIGK,BRIDGE, NEW JERSEY, ASSIGNOB (10 TAYLOR- WHABTON IRON AND STEEL COMPANY, 01' HIGH BRIDGE, NEW

JERSEY, A COB- am'rnon or resume nanamasn srann.

No Drawing.

My invention relates to the treatment of iron and steel alloys and more particularly manganese steel.

Objects of the invention are to provide for increased strength, and especially greater resistance to abrasive wear, of manganese steel shapes or articles, whether formed by casting or working or both, without impairing the toughness and ductility of the metal.

The nature of my invention consists in sealing manganese steel castings or forgings in the presence of case hardening or cementation material, effecting the case hardening during the heating operation in heat treatment, and quenching the case hardening product under conditions conducive to minimum By varying the material as to its components and their relative proportions, and by regulating the time the charge is held at heat, the depth and nature of the case hardening can readily be controlled.

According tomy invention, I provide for case carbonizing, case boronizing, or both, by subjecting the casting or forging to the action of carbonizing or boronizing materials, or a mixture thereof, while sealed against the atmosphere, during the heating stagesin heat treatment. Examples of materials ap )ropriate for the purpose are barium carl;onat.e (BaCO,) and charcoal or coke; bone in a finely divided state, In practice, the casting or forging and the charge are sealed in a container, or in-a covering, the nature of which will depend upon the size andshape of the article and whether it is be ing treated singly or in quantities, but which, by preference, will be adapted to adngt of quenching of the article or articles with ittlc An example is application, Ser.

oxid or boric alloy,

or no exposure to the air. disclosed in my co-pendmg No; 91,113. I

strength and wear resistive Application filed February 27, 1928. Serial No. 91,267.

My invention applies to high per cent manganese steel mercial manganese steel, that is to say, steel having a manganese content anging from live to twenty per cent and p'feferably eleven to fourteen per cent. 2 a

In some cases I propose to line the molds with finely divided boric oxid or boric alloy in admixture with various reducing sub stances and utilize the heat of casting to fuse boron into the surface of highper cent manganese steel. 7

Having described my invention, I claim L. The method of imparting greater strength and wear resistive properties to manganese steel without impairing the toughness and ductility of the metal, which consists the regular heat treatment, and quenching under conditions conducive to minimum exposure to air. 1

2. The method of imparting greater properties to manganese steel without impairing its toughness and ductility, which consists in packing the shape with cementing material in a container and, while so sealed against exposure, heat treating in me regular way, and then quenching.

3. The method of imparting greater strength and wear resistive properties to manganese steel without impairing its toughness and ductility, which consists in sealing the shape in the presence of tinely divided boric oxid and a reducing agent, and. while so sealed, heating it in stages in the regular order of heat treatment, and then quenching.

In testimony whereof I affix my signature.

VAN CORTRIGHT MEKEEL.

or what-is known as comfill till

in case hardening the shape during 

